1. Field of the Invention
The field of the invention is that of clutching means for providing drive between axially aligned members and is particularly adapted for tapping attachments. The exemplary form of the invention is embodied in a tapping attachment of the type having free axial float and providing for both direct and reverse drive. Improvements are provided in the device as described in detail herein, particularly adapting it for substantially frictionless drive of the tapping spindle. The drive is through clutch means which provides for engagement and disengagement without chattering. The drive is through ball members engageable with splines of special configuration to accommodate the purposes described hereinafter.
2. Description of the Prior Art
The background of the invention with respect to tapping attachments is exemplified in prior patents of this inventor U.S. Pat. Nos. 3,002,206; 3,041,893; 3,397,588; 3,717,392; and 3,791,756, which are hereby incorporated herein by reference. Reference is also made to U.S. Pat. No. 2,325,184. The background patents disclose the characteristics of tapping attachments having free axial float and direct and reverse drive.
U.S. Pat. No. 3,002,206 shows a type of spindle suspension similar to that disclosed herein. U.S. Pat. No. 3,397,588 discloses a type of construction wherein for the direct drive there is provided a spring biased clutch driver member which functions to eliminate chattering, when the clutch engages or disengages for direct drive. A similar clutch driver member may be and has been embodied in attachments having reverse drive as in U.S. Pat. No. 3,717,892. The herein invention improves particularly on the clutch driver means and its cooperation with the drive means and the spindle. The invention is an improvement of the structure of application Ser. No. 520,409 filed Nov. 4, 1974, which is hereby incorporated herein by reference. U.S. Pat. Nos. 3,041,893; 3,397,588; and 3,717,892 are also incorporated herein by reference.